Adhesive sealant to install Flexible solar panels on roof

[RC Pilot Jim]

3M Marine adhesive sealant "Fast Cure" 4000 UV Medium strength. Tube size 10 ounces.

Description:
..."High quality adhesive sealant has excellent adhesion to a variety of substrates including wood, fiberglas, metal and most plastics above and below the waterline. The adhesive sealant is designed to withstand UV exposure without the change of color (white ). This adhesive sealant forms, a firm, rubbery watertight seal that is resistant to stresses caused by joint movement. Its superior formulation withstands weathering, salt water, and fresh water environments.

Remove hardened sealant with razor blade, knife, wire then sand the the remainder off surface,

Buy at West Marine - $15.00/tube + tax = $17.70 or online.

Westmarine manager suggested a thin bead around the perimeter of the panel. I was going to add a criss-cross bead in the middle to alleviate a "ballooning" effect. Westmarine manager didn't believe that was necessary. (I always over-engineer everything)

 

[fish more]

If you use this product to glue panels to roof, suggest to leave a gap or two for water condensation drainage. Just a thought.

 

[RC Pilot Jim]

Good idea...maybe a small gap on either side.

 

[billharr]

Would a gap guarantee water under the panel when it rains?

 

[buckland]

BTW what panels did you buy and from where? I have a 90 watt regular glass/aluminum frame and wondered what the durability of the flex type was... sure is an attractive solution if it holds up.... and would go that way if it is a good investment.

 

[RC Pilot Jim]

Actually I haven't ordered yet. My plan was to buy "Renology" until I read the reply thread on DrJ's original post "Measured FWC Power Use" ..than I read the reply on Global Solar ..http://www.globalsolar.com/products/flexible-modules/rv

Checking that one out now.

 

[camper101]

Good to know about the adhesive, thanks.

I've got one of those Global Solar panels that I'm slowly getting around to installing. Can't say I know much about solar, but I've heard good things about the panels from a couple of people on the forums. If you move faster than me I'll be interested to see your install... I'm still figuring out some final details/parts for the hole in the roof (weather and time constraints have slowed me down - but that's a good thing). All I could find were 90 watt panels on eBay, which should be plenty for me.

I'm curious if you'd scuff up the roof before applying adhesive? I don't know if it's better to stick with the smooth roof (one piece roof on a 2012 camper) or do some light sanding or Scotchbrite.

 

[billharr]

I have been looking at the Global Solar panel like the light weight. The one I have seen have a peel and stick back. This one on Ebay has a lot of pictures.



Any one know of a review between the Global, Renogy and the rigid panels? Cost is very close between them when you add the cost of building a mount for the rigid panels.

 

[DrJ]

I've bought several panels from eBay. All 3 of mine are from this seller:
discountsolar
Just look up Semi-flexible 120 watt panels

Here are some pictures:

These panels put out a higher voltage - 22 volts - when they have good sunlight. You might need a MPPT charge controller because of increased voltage.
The positive side is that the increased voltage makes the voltage drop through the FWC roof solar plug minimal.
They are also super easy to add a second or third panel like I ended up doing. You just need a branch connector and hook them up. So if you don't have enough power, just add another one. And your voltage remains higher so the voltage drop is minimal.

I think they make a 100, 120, 135 or 150 watt.

I have two of his 120 watts and one 100 watt.

I learned about his 120 watt panels after I had already installed the 100 watt one. Otherwise I would have done them all 120 watts.

 

[billharr]

DrJ are your panels glued down? How long have you had them?

 

[DrJ]

My panels are glued down.
I've had them on for over 6 months now.

I used a heavy duty construction adhesive from the hardware store. It has worked great. I've tried pulling them up and they are on really tight. I'm sure I could pry them up if I really wanted to.

But it works great for me. I get my share of wind where I live. They have never budged at high winds or 75mph highway speeds.

Between the three, I frequently see 15-16 amps of charging. This means I can run my compressor fridge at 4-5 amps and still charge at around 10-12 amps.

I'll try to take a picture of my current roof top and post it later.

 

[Beach]

Camper101, I would clean the roof thoroughly, maybe even a light solvent cleaning to remove oil or grease. You could do a small test blob with the adhesive and give a good pull to see how well adhered it is before the actual install.

 

[RC Pilot Jim]

Testing is good idea.

 

[RC Pilot Jim]

Yesterday I "measured 3 times", came up with a plan.
My plan was to set the panel 7 inches in from the side edge of the roof and 10 inches back from the front. With the roof solar plug directly behind the panel - Leaving room on the passenger side for a second panel.

and tested the panel. It works.
NOTE
You will notice their is a protective plastic covering on the panel. To test it you need to carefully remove it. After testing - put this "saran wrap" covering back on the panels to protect them from the glue. It wii be removed before panel is plugged in.

Today was the big day to get it done.

1. Washed the roof.
2. Acetone-d (4000UV adhesive instructed me to use acetone to make sure surface was completely clean) the section where the panel will lie.
3. Washed any residue off with plain water.
4. Made my marks with pencil and blue painters tape to position it square.
5, Set up two ladders - you will need a second person to help position it between your marks in the front.
6. Tested carrying it up the ladder without brushing adhesive on the truck or camper.
7. Put on chemical safe gloves (ones worn to protect my hands from the acetone).
8. Opened tube applied the adhesive about 1/4" in from edge around the perimeter. and criss-crossed across the middle.
Used about 80% of a 10 oz tube.
9. Set it in place = DONE.
10. Since roof is not perfectly flat placed old towels on top of panel and weighted it down with bricks. Set camper aside to allow adhesive to completely cure - 24 hours.

Last to do when glue cures is install the adaptor plug, back truck into the sunshine and start monitoring the input on the Trimetric and take a drive to check the adhesion. So far it good...More in a few days.

 

[billharr]

Good job Jim. I did my 100w panel today, will try to get a report up later.


Bill

 

[photohc]

Nice Jim. Look forward to seeing the finished product in November. Harv

 

[takesiteasy]

Nice job. Thanks for the report.

 

[camper101]

Thanks indeed, and good example of testing: going up the ladder with a panel (not yet covered with adhesive). It's those little things...

 

[RC Pilot Jim]

Final Panel views

wiring connection - showing adaptor. There is only about 2" side-to-side "play" in the cables so have decided not to glue the bundle to the roof at least for now.. The plug connection is taped with electrical tape to keep out any water

View from Front. Room for a second panel over passenger side.

Tomorrow is the test drive.

9/20/14
Test drive went well. 40 mile round trip to/from the flying field. Weather was cloudy. Turned on the refer, Net Amp draw - 2 amps. Even in the carport the panel is generating - half an amp from reflected light off my neighbors roof..

 

[DrJ]

Jim,
That looks great.
You are inspiring me to clean up all my wires on my install too.